iphone 4s drops signal on T- Mobile USA

am also having the same problem with my new iphone 4s factory unlocked. eventhough i have simple moblie(u.s.a) the network shows tmobile and signal always drop to some times 1 or 0 anytime i end a call. apart from the signal droping after calls, the signal also drops randomly for no reason, but doesn't stay long in the search mode, signal comes right back after 1 or 2 seconds.don't know whether is the phone or the network so am planning on returning it on monday. i luv this phone so much any suggestions or help to save my new love.

T-Mobile is NOT a supported carrier in the US. Their network is not fully compatible with the iPhone.

You'll have to take it up with T-Mobile.

max did you have this problem before or it just started after an update. had my phone after the new 5.1...update so dont really know whether this problem existed before, but i have same problem like you and i don't know whether it's the phone or just a software or network issue. still have some time to return the phone so i want know what to do. if you didn't have the problem before, then i guess it will be from an update. pls let me know your response. or anyone who have an idea or suggestions...

Even if it does have something to do with the way iOS is interacting with the T-Mobile network, you're wasting your breath here. The simple fact is, Apple does not support the iPhone on T-Mobile. If you want to use it on T-Mobile, you'll have to take it up with them.

There are 3 supported nationwide carriers with the iPhone. This is one of the risks you take when you opt to use the ONLY nationwide network in the U.S. that is not supported.

well from all indications i think it's a software problem. am going to try a diffrent network sim today and see if it does same thing.

Do yourself a favor. Use a SIM from a SUPPORTED carrier. In the U.S. this means AT&T.

ok will try that too...thx but just to let you that it i have the factory unlocked version 4s straight from app store. so it will be very unresonable for apple to claim that the 4s is a world phone if it can not work fully on tmobile apart the 3g which we know it dosn't support.

Apple claims it will work on any compatible GSM network. The T-Mobile network in the U.S. is KNOWN NOT to be compatible with ANY version of the iPhone. If a network is compatible, but unsupported, that means it's up to the carrier to get it working if they can.

If you use T-Mobile, you also will not get:

MMS messaging

FaceTime

Visual Voice Mail.

Siri may or may not behave as expected due to the slow data network speeds.

If you insist on using it with T-Mobile, take it up with them. Apple never made a claim that an iPhone would would on any GSM network on the planet regardless of whether or not it's compatible.

There are 3 national carriers in the US that support the iPhone. If you can't get it working with T-Mobile, switch carriers. Though if you want to use the phone you already purchased, you're limited to AT&T.

so today i tried my factory unlocked iphone 4s on at&t and the signal never drop after i ended a call like it does on tmobile. i also tried it on h20 and again the signal never drop after i ended a call so finnally i now know there is nothing wrong with my iphone. it's just some thing with either tmobile network or the latest apple update but i believe it is the update because i use to have an iphone on tmobile network which didn't act like this. with the at&t sim my phone was even getting more signal than the actual at&t iphone. was thinking about returning the iphone but after i did the swipe of sim i have decided to keep it. happy now.

I purchased the iphone 4s within a week of it's release. I have AT&T as my carrier. I have had NO problems until about 3 days ago and the phone goes into search mode constantly! I try to make a call and within 30 seconds the call is dropped and it is in search mode again. When not making calls it goes from having a signal, full bars, AT&T and either 3G or wi-fi signal to search mode about every 30 seconds. I haven't been able to make a call ever since this problem started. I have been traveling and haven't plugged my phone in to check for any upgrades to software until last night and when I did it had the correct update.

Please make any suggestions you can.

This is normal.

The reason why this is happening is because the 4S has 3G turned on by default and there isn't a way to turn off the 3G because they got rid of the toggle button on the 4S.

Each time when you hang up and the reception drops, that's because it's looking for a 3G signal and when it doesn't find one it'll resorts to Edge. If you have your iPhone 4 still, turn on the 3G and you'll get the same result with drop reception as on the 4S. Again this is normal behavior

iOS 5.1 brings back the 3G toggle button, which will fix this problem when you toggle it off.

I hope this helps.

<Edited by Host>

@KiltedTim

Hi there,

I have also iPhone 4S factory unlocked, using Tmobile and I'm having problems with droping calls, and I'm not able to get more than 3 bars after all the 3G turning off and upgrading the phone.... but I found a help with sending MMS on Tmobile:

Re: MMS factory unlocked iPhone 4s ???

The official T-mobile configuration settings are as follows:

Instructions:

To set up Internet and picture messaging on your device, follow these steps:

Internet setup

1. From the main screen, scroll to and select Settings.
2. Select General, Network.
3. Verify that Data Roaming is set to On.
4. 3G Enable is Off
5. Select Cellular Data Network.

   Note: In software versions prior to 2.0, Cellular Data Network is called EDGE.

6. In the APN field, enter epc.tmobile.com.
7. Leave the Username and Password fields blank.
8. Press the Home button to save the APN and exit to the main screen.
9. Select Settings.
10. Select Wi-Fi.
11. Select off.
12. Test the connection by opening the Safari Web browser.

Picture messaging (MMS) setup

1. From the main screen, select Settings.
2. Select General, Network.
3. Select Cellular Data Network.

¿ Note: In software versions prior to 2.0, Cellular Data Network is called EDGE.

1. In the MMS section, enter epc.tmobile.com in the APN field.
2. Leave the Username and Password fields blank.
3. In the MMSC field, enter mms.msg.eng.t-mobile.com/mms/wapenc.
4. Leave the MMS Proxy, MMS Max Message Size, and MMS UA Prof URL fields blank.
5. Press the Home button to return to the main screen.
6. Turn the device off and back on.
7. From the main screen, select Settings.
8. Select Messages, MMS.
9. Verify that MMS Messaging is set to On.
10. Test the settings by sending a picture message to your own mobile number.

NOTE: The handset must be turned off and then back on following MMS configuration. Until this is done you will not see an option to send an MMS. Verify MMS is enabled:

1. Tap Settings
2. Tap Messages
3. Tap MMS
4. Set MMS Messaging to On

Send a Picture Message:

1. Create a new Text Message
2. There will be a Camera icon on the screen.
3. Tap the Camera icon to add a Picture to the Message.

Good luck!!

dagmand

OK. Good luck with that. As we've already stated. T-Mobile in the US is NOT a supported carrier.